Federal courts have the right to nullify laws that they feel are violating the Constitution. These cases then often head to the higher court and possibly eventually to the Supreme Court if they are appealed far enough.
Explanation:
After examining them, they may nullify them if they assume the laws are undemocratic. Of course, there can be a discussion among the members of a court over whether a given law is unconstitutional. after reviewing them, they may revoke them if they feel the laws are illegal. Of course, there can be debate among the members of a court over whether a given law is undemocratic.